HMPID/AliHMPIDv2.cxx

   1 // **************************************************************************
   2 // * Copyright(c) 1998-1999, ALICE Experiment at CERN, All rights reserved. *
   3 // *                                                                        *
   4 // * Author: The ALICE Off-line Project.                                    *
   5 // * Contributors are mentioned in the code where appropriate.              *
   6 // *                                                                        *
   7 // * Permission to use, copy, modify and distribute this software and its   *
   8 // * documentation strictly for non-commercial purposes is hereby granted   *
   9 // * without fee, provided that the above copyright notice appears in all   *
  10 // * copies and that both the copyright notice and this permission notice   *
  11 // * appear in the supporting documentation. The authors make no claims     *
  12 // * about the suitability of this software for any purpose. It is          *
  13 // * provided "as is" without express or implied warranty.                  *
  14 // **************************************************************************
  15
  16
  17 #include "AliHMPIDv2.h"       //class header
  18 #include "AliHMPIDParam.h"    //StepManager()
  19 #include "AliHMPIDHit.h"      //Hits2SDigs(),StepManager()
  20 #include "AliHMPIDDigit.h"    //Digits2Raw(), Raw2SDigits()
  21 #include "AliHMPIDRawStream.h"  //Digits2Raw(), Raw2SDigits()
  22 #include "AliRawReader.h"     //Raw2SDigits()
  23 #include "AliTrackReference.h"
  24 #include <TVirtualMC.h>       //StepManager() for gMC
  25 #include <TPDGCode.h>         //StepHistory()
  26 #include <AliStack.h>         //StepManager(),Hits2SDigits()78.6
  27 #include <AliLoader.h>        //Hits2SDigits()
  28 #include <AliRunLoader.h>     //Hits2SDigits()
  29 #include <AliMC.h>            //StepManager()
  30 #include <AliRun.h>           //CreateMaterials()
  31 #include <AliMagF.h>          //CreateMaterials()
  32 #include "AliGeomManager.h"   //AddAlignableVolumes()
  33 #include <AliCDBEntry.h>      //CreateMaterials()
  34 #include <AliCDBManager.h>    //CreateMaterials()
  35 #include <TF1.h>              //DefineOpticalProperties()
  36 #include <TF2.h>              //DefineOpticalProperties()
  37 #include <TGeoGlobalMagField.h>
  38 #include <TGeoPhysicalNode.h> //AddAlignableVolumes()
  39 #include <TLorentzVector.h>   //IsLostByFresnel()
  40 #include <TTree.h>
  41
  42 ClassImp(AliHMPIDv2)
  43 //++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
  44 void AliHMPIDv2::AddAlignableVolumes()const
  45 {
  46 // Associates the symbolic volume name with the corresponding volume path. Interface method from AliModule invoked from AliMC
  47 // Arguments: none
  48 //   Returns: none
  49
  50   AliGeomManager::ELayerID idHMPID = AliGeomManager::kHMPID;
  51   Int_t modUID, modnum = 0;
  52
  53   TGeoHMatrix *pGm = new TGeoHMatrix;
  54   Double_t trans[3]={0.5*131.24,0.5*126.16,0};                            //translation from LORS to TGeo RS (half size AllX, half size allY,0)
  55   pGm->SetTranslation(trans);
  56
  57   Double_t ph[7]={10.,10., 30.,30.,30. ,50.,50};
  58
  59   for(Int_t iCh=AliHMPIDParam::kMinCh;iCh<=AliHMPIDParam::kMaxCh;iCh++) {
  60     modUID = AliGeomManager::LayerToVolUID(idHMPID,modnum++);
  61     if(!gGeoManager->SetAlignableEntry(Form("/HMPID/Chamber%i",iCh),Form("ALIC_1/Hmp_%i",iCh),modUID))
  62             AliError("AliHMPIDv3::Unable to set alignable entry!!");  //aligment without AliCluster3D
  63     //Get Tracking To Local matricies for alignment with AliCluster3D
  64     TGeoPNEntry *eCh = gGeoManager->GetAlignableEntryByUID(modUID);
  65     TGeoHMatrix *globMatrix = eCh->GetGlobalOrig();
  66
  67     //Double_t phi = 20.0 * ((iCh+1) / 3) + 10.0;
  68     Double_t phi = ph[iCh];
  69     TGeoHMatrix *t2l  = new TGeoHMatrix();
  70     t2l->RotateZ(phi);
  71     t2l->MultiplyLeft(&(globMatrix->Inverse()));
  72     eCh->SetMatrix(t2l);
  73   }//iCh loop
  74 }
  75 //++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
  76 void AliHMPIDv2::CreateMaterials()
  77 {
  78 // Definition of available HMPID materials
  79 // Arguments: none
  80 //   Returns: none
  81   AliDebug(1,"Start v2 HMPID.");
  82
  83     //clm update material definition later on from Antonello
  84
  85 //data from PDG booklet 2002     density [gr/cm^3] rad len [cm] abs len [cm]
  86   Float_t   aAir[4]={12,14,16,36}    ,   zAir[4]={6,7,8,18} ,   wAir[4]={0.000124,0.755267,0.231781,0.012827} , dAir=0.00120479; Int_t nAir=4;//mixture 0.9999999
  87   Float_t aC6F14[2]={ 12.01 , 18.99} , zC6F14[2]={ 6 , 9}   , wC6F14[2]={6 , 14} , dC6F14=1.68    ; Int_t nC6F14=-2;
  88   Float_t  aSiO2[2]={ 28.09 , 15.99} ,  zSiO2[2]={14 , 8}   ,  wSiO2[2]={1 ,  2} ,  dSiO2=2.64    ; Int_t  nSiO2=-2;
  89   Float_t   aCH4[2]={ 12.01 ,  1.01} ,   zCH4[2]={ 6 , 1}   ,   wCH4[2]={1 ,  4} ,   dCH4=7.17e-4 ; Int_t   nCH4=-2;
  90 // not necessary...PCB properties instead! Float_t   aCsI[2]={132.90 ,126.90} ,   zCsI[2]={55 ,53}   ,   wCsI[2]={1 ,  1} ,   dCsI=0.1     ; Int_t   nCsI=-2;
  91
  92   Float_t     aRoha = 12.01 ,   zRoha =  6 ,  dRoha =  0.10    ,   radRoha = 18.80 , absRoha =  86.3/dRoha; //special material- quasi quartz
  93   Float_t       aCu = 63.55 ,   zCu   = 29 ,  dCu   =  8.96    ,   radCu   =  1.43 , absCu   = 134.9/dCu  ;
  94   Float_t        aW =183.84 ,   zW    = 74 ,  dW    = 19.30    ,   radW    =  0.35 , absW    = 185.0/dW   ;
  95   Float_t       aAl = 26.98 ,   zAl   = 13 ,  dAl   =  2.70    ,   radAl   =  8.90 , absAl   = 106.4/dAl  ;
  96   Float_t       aAr = 39.94 ,   zAr   = 18 ,  dAr   =  1.396e-3,   radAr   =  14.0 , absAr   = 117.2/dAr  ;
  97
  98     Int_t   matId=0;                           //tmp material id number
  99     Int_t   unsens =  0, sens=1;               //sensitive or unsensitive medium
 100     Int_t   itgfld = ((AliMagF*)TGeoGlobalMagField::Instance()->GetField())->Integ(); //type of field intergration 0 no field -1 user in guswim 1 Runge Kutta 2 helix 3 const field along z
 101     Float_t maxfld = ((AliMagF*)TGeoGlobalMagField::Instance()->GetField())->Max();   //max field value
 102     Float_t tmaxfd = -10.0;                    //max deflection angle due to magnetic field in one step
 103     Float_t deemax = - 0.2;                    //max fractional energy loss in one step
 104     Float_t stemax = - 0.1;                    //max step allowed [cm]
 105     Float_t epsil  =   0.001;                  //abs tracking precision [cm]
 106     Float_t stmin  = - 0.001;                  //min step size [cm] in continius process transport, negative value: choose it automatically
 107
 108     // PCB copmposed mainly by G10 (Si,C,H,O) -> CsI is negligible (<500nm thick)
 109     // So what is called CsI has the optical properties of CsI, but the composition of G-10 (for delta elec, etc production...)
 110
 111     Float_t aG10[4] = {28.09,12.01,1.01,16.00};
 112     Float_t zG10[4] = {14.,  6.,  1.,  8.};
 113     Float_t wG10[4] = {0.129060,0.515016,0.061873,0.294050};
 114     Float_t dG10    = 1.7;
 115     Int_t   nG10    = 4;
 116
 117     AliMixture(++matId,"Air"  ,aAir  ,zAir  ,dAir  ,nAir  ,wAir  ); AliMedium(kAir  ,"Air"  ,matId, unsens, itgfld, maxfld, tmaxfd, stemax, deemax, epsil, stmin);
 118     AliMixture(++matId,"C6F14",aC6F14,zC6F14,dC6F14,nC6F14,wC6F14); AliMedium(kC6F14,"C6F14",matId, unsens, itgfld, maxfld, tmaxfd, stemax, deemax, epsil, stmin);
 119     AliMixture(++matId,"SiO2" ,aSiO2 ,zSiO2 ,dSiO2 ,nSiO2 ,wSiO2 ); AliMedium(kSiO2 ,"SiO2" ,matId, unsens, itgfld, maxfld, tmaxfd, stemax, deemax, epsil, stmin);
 120     AliMixture(++matId,"CH4"  ,aCH4  ,zCH4  ,dCH4  ,nCH4  ,wCH4  ); AliMedium(kCH4  ,"CH4"  ,matId, unsens, itgfld, maxfld, tmaxfd, stemax, deemax, epsil, stmin);
 121 //    AliMixture(++matId,"CsI"  ,aCsI  ,zCsI  ,dCsI  ,nCsI  ,wCsI  ); AliMedium(kCsI  ,"CsI"  ,matId,   sens, itgfld, maxfld, tmaxfd, stemax, deemax, epsil, stmin);//sensitive
 122     AliMixture(++matId,"CsI+PCB",aG10  , zG10, dG10,nG10   ,wG10   ); AliMedium(kCsI  ,"CsI"  ,matId,   sens, itgfld, maxfld, tmaxfd, stemax, deemax, epsil, stmin);//sensitive
 123
 124     AliMixture(++matId ,"Neo" ,aSiO2 ,zSiO2 ,dSiO2 ,nSiO2 ,wSiO2 ); AliMedium(kNeo  ,"Neo"  ,matId, unsens, itgfld, maxfld, tmaxfd, stemax, deemax, epsil, stmin); //clm neoceram
 125     AliMaterial(++matId,"Roha",aRoha,zRoha,dRoha,radRoha,absRoha);  AliMedium(kRoha ,"Roha" ,matId, unsens, itgfld, maxfld, tmaxfd, stemax, deemax, epsil, stmin); //Roha->honeycomb
 126
 127
 128     AliMaterial(++matId,"Cu"  ,aCu  ,zCu  ,dCu  ,radCu  ,absCu  );  AliMedium(kCu  ,"Cu"  , matId, unsens, itgfld, maxfld, tmaxfd, stemax, deemax, epsil, stmin);
 129     AliMaterial(++matId,"W"   ,aW   ,zW   ,dW   ,radW   ,absW   );  AliMedium(kW   ,"W"   , matId, unsens, itgfld, maxfld, tmaxfd, stemax, deemax, epsil, stmin);
 130     AliMaterial(++matId,"Al"  ,aAl  ,zAl  ,dAl  ,radAl  ,absAl  );  AliMedium(kAl  ,"Al"  , matId, unsens, itgfld, maxfld, tmaxfd, stemax, deemax, epsil, stmin);
 131     AliMaterial(++matId,"Ar"  ,aAr  ,zAr  ,dAr  ,radAr  ,absAr  );  AliMedium(kAr  ,"Ar"  , matId, unsens, itgfld, maxfld, tmaxfd, stemax, deemax, epsil, stmin);
 132
 133     //InitProperties();
 134
 135 }//void AliHMPID::CreateMaterials()
 136 //++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 137 //void AliHMPIDv2::InitProperties()
 138 //{
 139 /*
 140 * HMPID
 141 * ====
 142 *
 143 *       GAM   ELEC  NHAD   CHAD  MUON  EBREM MUHAB  EDEL  MUDEL MUPA ANNI BREM COMP DCAY DRAY HADR LOSS MULS PAIR PHOT RAYL
 144 * Quarz Window        (>1000 keV delta-electrons)
 145 HMPID  3  1.e-4 1.e-4 1.e-4  -1.   1.e-4 -1.   -1.    1.e-3 1.e-3 -1.  -1   -1   -1   -1   1    -1   1    -1   -1   -1   -1
 146 * Freon Radiator      (>  500 keV delta-electrons)
 147 HMPID  4  1.e-4 1.e-4 1.e-4  -1.   1.e-4 -1.   -1.    5.e-4 5.e-4 -1.  -1   -1   -1   -1   1    -1   1    -1   -1   -1   -1
 148 * Methane Gap         (>  100 keV delta-electrons)
 149 HMPID  5  5.e-5 1.e-5 1.e-4 -1.   1.e-4 -1.   -1.     1.e-4 1.e-4 -1.  -1   -1   -1   -1   1    -1   1    -1   -1   -1   -1
 150 * Sensitive Volume    (>  50 keV delta-electrons)
 151 HMPID  9  1.e-5 1.e-5 1.e-4  -1.   1.e-4 -1.   -1.    5.e-5 5.e-5 -1.  -1   -1   -1   -1   1    -1   1    -1   -1   -1   -1
 152 * CSI    (>  50 keV delta-electrons)
 153 HMPID  6  1.e-5 1.e-5 1.e-4  -1.   1.e-4 -1.   -1.    5.e-5 5.e-5 -1.  -1   -1   -1   -1   1    -1   1    -1   -1   -1   -1
 154 * PCB backplane   (>  50 keV delta-electrons)
 155 HMPID 12  1.e-5 1.e-5 1.e-4  -1.   1.e-4 -1.   -1.    5.e-5 5.e-5 -1.  -1   -1   -1   -1   1    -1   1    -1   -1   -1   -1
 156
 157     Int_t *idtmed = fIdtmed->GetArray();
 158     Int_t imed;
 159
 160     imed = kSiO2;   // * Quarz Window        (>1000 keV delta-electrons)
 161     gMC->Gstpar(idtmed[imed], "CUTGAM",1.e-4);
 162     gMC->Gstpar(idtmed[imed], "CUTELE",1.e-4);
 163     gMC->Gstpar(idtmed[imed], "CUTNEU",1.e-4);
 164     gMC->Gstpar(idtmed[imed], "CUTMUO",1.e-4);
 165     gMC->Gstpar(idtmed[imed], "DCUTE" ,1.e-3);
 166     gMC->Gstpar(idtmed[imed], "CUTHAD",1.e-3);
 167
 168     gMC->Gstpar(idtmed[imed], "DRAY",1);
 169     gMC->Gstpar(idtmed[imed], "LOSS",1);
 170
 171     imed = kC6F14;  // * Freon Radiator      (>  500 keV delta-electrons)
 172     gMC->Gstpar(idtmed[imed], "CUTGAM",1.e-4);
 173     gMC->Gstpar(idtmed[imed], "CUTELE",1.e-4);
 174     gMC->Gstpar(idtmed[imed], "CUTNEU",1.e-4);
 175     gMC->Gstpar(idtmed[imed], "CUTMUO",1.e-4);
 176     gMC->Gstpar(idtmed[imed], "DCUTE" ,5.e-4);
 177     gMC->Gstpar(idtmed[imed], "CUTHAD",5.e-4);
 178
 179     gMC->Gstpar(idtmed[imed], "DRAY",1);
 180     gMC->Gstpar(idtmed[imed], "LOSS",1);
 181
 182     imed = kCH4;  // * Methane Gap         (>  100 keV delta-electrons)
 183     gMC->Gstpar(idtmed[imed], "CUTGAM",5.e-5);
 184     gMC->Gstpar(idtmed[imed], "CUTELE",5.e-5);
 185     gMC->Gstpar(idtmed[imed], "CUTNEU",1.e-4);
 186     gMC->Gstpar(idtmed[imed], "CUTMUO",1.e-4);
 187     gMC->Gstpar(idtmed[imed], "DCUTE" ,1.e-4);
 188     gMC->Gstpar(idtmed[imed], "CUTHAD",1.e-4);
 189
 190     gMC->Gstpar(idtmed[imed], "DRAY",1);
 191     gMC->Gstpar(idtmed[imed], "LOSS",1);
 192
 193     imed = kCsI;  // * CSI    (>  50 keV delta-electrons)
 194     gMC->Gstpar(idtmed[imed], "CUTGAM",1.e-5);
 195     gMC->Gstpar(idtmed[imed], "CUTELE",1.e-5);
 196     gMC->Gstpar(idtmed[imed], "CUTNEU",1.e-4);
 197     gMC->Gstpar(idtmed[imed], "CUTMUO",1.e-4);
 198     gMC->Gstpar(idtmed[imed], "DCUTE" ,5.e-5);
 199     gMC->Gstpar(idtmed[imed], "CUTHAD",5.e-5);
 200
 201     gMC->Gstpar(idtmed[imed], "DRAY",1);
 202     gMC->Gstpar(idtmed[imed], "LOSS",1);
 203
 204     imed = kAl;  // * Alluminium    (>  50 keV delta-electrons)
 205     gMC->Gstpar(idtmed[imed], "CUTGAM",1.e-5);
 206     gMC->Gstpar(idtmed[imed], "CUTELE",1.e-5);
 207     gMC->Gstpar(idtmed[imed], "CUTNEU",1.e-4);
 208     gMC->Gstpar(idtmed[imed], "CUTMUO",1.e-4);
 209     gMC->Gstpar(idtmed[imed], "DCUTE" ,5.e-5);
 210     gMC->Gstpar(idtmed[imed], "CUTHAD",5.e-5);
 211
 212     gMC->Gstpar(idtmed[imed], "DRAY",1);
 213     gMC->Gstpar(idtmed[imed], "LOSS",1);
 214
 215     imed = kCu;  // * Copper       (>  50 keV delta-electrons)
 216     gMC->Gstpar(idtmed[imed], "CUTGAM",1.e-5);
 217     gMC->Gstpar(idtmed[imed], "CUTELE",1.e-5);
 218     gMC->Gstpar(idtmed[imed], "CUTNEU",1.e-4);
 219     gMC->Gstpar(idtmed[imed], "CUTMUO",1.e-4);
 220     gMC->Gstpar(idtmed[imed], "DCUTE" ,5.e-5);
 221     gMC->Gstpar(idtmed[imed], "CUTHAD",5.e-5);
 222
 223     gMC->Gstpar(idtmed[imed], "DRAY",1);
 224     gMC->Gstpar(idtmed[imed], "LOSS",1);
 225
 226     imed = kW;  // * Tungsten     (>  50 keV delta-electrons)
 227     gMC->Gstpar(idtmed[imed], "CUTGAM",1.e-5);
 228     gMC->Gstpar(idtmed[imed], "CUTELE",1.e-5);
 229     gMC->Gstpar(idtmed[imed], "CUTNEU",1.e-4);
 230     gMC->Gstpar(idtmed[imed], "CUTMUO",1.e-4);
 231     gMC->Gstpar(idtmed[imed], "DCUTE" ,5.e-5);
 232     gMC->Gstpar(idtmed[imed], "CUTHAD",5.e-5);
 233
 234     gMC->Gstpar(idtmed[imed], "DRAY",1);
 235     gMC->Gstpar(idtmed[imed], "LOSS",1);
 236
 237 }*/
 238 //++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 239 void AliHMPIDv2::CreateGeometry()
 240 {
 241 //Creates detailed geometry simulation (currently GEANT volumes tree)
 242   AliDebug(1,"Start main.");
 243   if(!gMC->IsRootGeometrySupported()) return;
 244
 245  Double_t cm=1,mm=0.1*cm,um=0.001*mm;//default is cm
 246
 247   TGeoMedium *al   =gGeoManager->GetMedium("HMPID_Al");
 248   TGeoMedium *ch4  =gGeoManager->GetMedium("HMPID_CH4");
 249   TGeoMedium *roha =gGeoManager->GetMedium("HMPID_Roha");
 250   TGeoMedium *neoc =gGeoManager->GetMedium("HMPID_Neo");
 251   TGeoMedium *c6f14=gGeoManager->GetMedium("HMPID_C6F14");
 252   TGeoMedium *sio2 =gGeoManager->GetMedium("HMPID_SiO2");
 253   TGeoMedium *cu   =gGeoManager->GetMedium("HMPID_Cu");
 254   TGeoMedium *w    =gGeoManager->GetMedium("HMPID_W");
 255   TGeoMedium *csi  =gGeoManager->GetMedium("HMPID_CsI");
 256   TGeoMedium *ar   =gGeoManager->GetMedium("HMPID_Ar");
 257
 258   TGeoVolume *hmp=gGeoManager->MakeBox ("Hmp",ch4,1681*mm/2, 1466*mm/2,(2*80*mm+2*60*mm)/2);//2033P1  z from p84 TDR
 259
 260   TString title=GetTitle();
 261   if(title.Contains("TestBeam")){
 262     gGeoManager->GetVolume("ALIC")->AddNode(hmp,0);
 263   }else{
 264     for(Int_t iCh=AliHMPIDParam::kMinCh;iCh<=AliHMPIDParam::kMaxCh;iCh++){//place 7 chambers
 265       TGeoHMatrix *pMatrix=new TGeoHMatrix;
 266       IdealPosition(iCh,pMatrix);
 267       gGeoManager->GetVolume("ALIC")->AddNode(hmp,iCh,pMatrix);
 268     }
 269   }
 270
 271   TGeoRotation *rot=new TGeoRotation("HwireRot"); rot->RotateY(90); //rotate wires around Y to be along X (initially along Z)
 272   TGeoVolume *sbo=gGeoManager->MakeBox ("Hsbo",ch4  , 1419*mm/2 , 1378.00*mm/2 ,   50.5*mm/2);//2072P1
 273   TGeoVolume *cov=gGeoManager->MakeBox ("Hcov",al   , 1419*mm/2 , 1378.00*mm/2 ,    0.5*mm/2);
 274   TGeoVolume *hon=gGeoManager->MakeBox ("Hhon",roha , 1359*mm/2 , 1318.00*mm/2 ,   49.5*mm/2);
 275   TGeoVolume *rad=gGeoManager->MakeBox ("Hrad",c6f14, 1330*mm/2 ,  413.00*mm/2 ,   24.0*mm/2); //2011P1
 276   TGeoVolume *neo=gGeoManager->MakeBox ("Hneo",neoc , 1330*mm/2 ,  413.00*mm/2 ,    4.0*mm/2);
 277   TGeoVolume *win=gGeoManager->MakeBox ("Hwin",sio2 , 1330*mm/2 ,  413.00*mm/2 ,    5.0*mm/2);
 278   TGeoVolume *si1=gGeoManager->MakeBox ("Hsi1",sio2 , 1330*mm/2 ,    5.00*mm/2 ,   15.0*mm/2);
 279   TGeoVolume *si2=gGeoManager->MakeBox ("Hsi2",neoc ,   10*mm/2 ,  403.00*mm/2 ,   15.0*mm/2);
 280   TGeoVolume *spa=gGeoManager->MakeTube("Hspa",sio2 ,    0*mm   ,    5.00*mm   ,   15.0*mm/2);
 281   TGeoVolume *fr4=gGeoManager->MakeBox ("Hfr4",ch4  , 1407*mm/2 , 1366.00*mm/2 ,   15.0*mm/2);//2043P1
 282   TGeoVolume *f4a=gGeoManager->MakeBox ("Hf4a",al   , 1407*mm/2 , 1366.00*mm/2 ,   10.0*mm/2);
 283   TGeoVolume *f4i=gGeoManager->MakeBox ("Hf4i",ch4  , 1323*mm/2 , 1296.00*mm/2 ,   10.0*mm/2);
 284   TGeoVolume *col=gGeoManager->MakeTube("Hcol",cu   ,    0*mm   ,  100.00*um   , 1323.0*mm/2);
 285   TGeoVolume *sec=gGeoManager->MakeBox ("Hsec",ch4  ,  648*mm/2 ,  411.00*mm/2 ,   6.2*mm/2);//sec=gap
 286
 287   Double_t cellx=8.04*mm,celly=8.4*mm;  Int_t nPadX=80, nPadY=48;
 288   TGeoVolume *gap=gGeoManager->MakeBox ("Hgap",ch4  ,  cellx*nPadX/2 ,  celly*nPadY/2 ,    6.2*mm/2); //x=8.04*80 y=8.4*48 z=pad+pad-ano+marign 2006p1
 289   TGeoVolume *row=        gap->Divide  ("Hrow",2,nPadY,0,0);//along Y->48 rows
 290   TGeoVolume *cel=        row->Divide  ("Hcel",1,nPadX,0,0);//along X->80 cells
 291   TGeoVolume *cat=gGeoManager->MakeTube("Hcat",cu   ,    0.00*mm   ,   50.00*um   ,    cellx/2);
 292   TGeoVolume *ano=gGeoManager->MakeTube("Hano",w    ,    0.00*mm   ,   20.00*um   ,    cellx/2);
 293   TGeoVolume *pad=gGeoManager->MakeBox ("Hpad",csi  ,    7.54*mm/2 ,    7.90*mm/2 ,    1.7*mm/2); //2006P1 PCB material...
 294   TGeoVolume *fr1=gGeoManager->MakeBox ("Hfr1",al   , 1463*mm/2 , 1422.00*mm/2 ,   58.3*mm/2);//2040P1
 295   TGeoVolume *fr1up=gGeoManager->MakeBox ("Hfr1up",ch4,(1426.00-37.00)*mm/2 , (1385.00-37.00)*mm/2 ,    20.0*mm/2);//2040P1
 296   TGeoVolume *fr1perUpBig=gGeoManager->MakeBox ("Hfr1perUpBig",ch4,1389*mm/2,35*mm/2,10*mm/2);
 297   TGeoVolume *fr1perUpSma=gGeoManager->MakeBox ("Hfr1perUpSma",ch4,35*mm/2,(1385-37-2*35)*mm/2,10*mm/2);
 298         TGeoVolume *fr1perDowBig=gGeoManager->MakeBox ("Hfr1perDowBig",ch4,1389*mm/2,46*mm/2,2.3*mm/2);
 299   TGeoVolume *fr1perDowSma=gGeoManager->MakeBox ("Hfr1perDowSma",ch4,46*mm/2,(1385-37-2*46)*mm/2,2.3*mm/2);
 300
 301         TGeoVolume *ppf=gGeoManager->MakeBox ("Hppf",al   ,  648*mm/2 ,  411.00*mm/2 ,   38.3*mm/2);//2001P2
 302   TGeoVolume *lar=gGeoManager->MakeBox ("Hlar",ar   ,  181*mm/2 ,   89.25*mm/2 ,   38.3*mm/2);//2001P2
 303   TGeoVolume *smo=gGeoManager->MakeBox ("Hsmo",ar   ,  114*mm/2 ,   89.25*mm/2 ,   38.3*mm/2);//2001P2
 304
 305
 306
 307         TGeoVolume *fr3=   gGeoManager->MakeBox("Hfr3",          al,  1463*mm/2,  1422*mm/2,  34*mm/2);//2041P1
 308    TGeoVolume *fr3up=    gGeoManager->MakeBox("Hfr3up",     ch4, 1323*mm/2,  1282*mm/2,  20*mm/2);//2041P1
 309    TGeoVolume *fr3down=gGeoManager->MakeBox("Hfr3down", ch4, 1437*mm/2,  1370*mm/2,  14*mm/2);//2041P1
 310
 311
 312
 313 // ^ Y   z=         z=-12mm      z=98.25mm               ALIC->7xHmp (virtual)-->1xHsbo (virtual) --->2xHcov (real) 2072P1
 314 // |  ____________________________________                                    |                   |-->1xHhon (real) 2072P1
 315 // | |   ______     ____          ______  |                                   |
 316 //   |  |      |   |    |   *    |      | |                                   |->3xHrad (virtual) --->1xHneo (real) 2011P1
 317 //   |  |50.5mm|   |24mm|   *    |45.5mm| |                                   |                   |-->1xHwin (real) 2011P1
 318 //   |  |      |   |    |   *    |      | |                                   |                   |-->2xHsi1 (real) 2011P1
 319 //   |  |      |   |____|   *    |______| |                                   |                   |-->2xHsi2 (real) 2011P1
 320 //   |  |      |    ____    *     ______  |                                   |                   |->30xHspa (real) 2011P1
 321 //   |  |      |   |    |   *    |      | |                                   |
 322 //   |  |      |   |    |   *    |      | |                                   |->1xHfr4 (vitual) --->1xHf4a (real)---->1xHf4i(virtual) 2043P1
 323 //   |  |  sb  |   | rad|   *    |      | |                                   |                  |-->322xHcol (real) 2043P1
 324 //   |  |      |   |____|   *    |______| |                                   |
 325 //   |  |      |    ____    *     ______  |                                   |->1xHfr1 (real) --> 6xHppf(real) ---->8xHlar (virtual) 2001P1
 326 //   |  |      |   |    |   *    |      | |                                   |                                     |--->8xHsmo (virtual) 2001P1
 327 //   |  |      |   |    |   *    |      | |                                   |
 328 //   |  |      |   |    |   *    |      | |                                   |-> 6xHgap (virtual) --->48xHrow (virtual) -->80xHcel (virtual) -->4xHcat (real) from p84 TDR
 329 //   |  |______|   |____|   *    |______| |                                                                                                  |-->2xHano (real) from p84 TDR
 330 //   |____________________________________|                                                                                                  |-->1xHpad (real) from p84 TDR
 331 //                                                       --->Z
 332   hmp->AddNode(sbo ,1,new TGeoTranslation(   0*mm,   0*mm, -73.75*mm));                     //p.84 TDR
 333      sbo->AddNode(hon ,1,new TGeoTranslation(  0*mm,0*mm,      0*mm)); //2072P1
 334      sbo->AddNode(cov ,1,new TGeoTranslation(  0*mm,0*mm,    +25*mm));
 335      sbo->AddNode(cov ,2,new TGeoTranslation(  0*mm,0*mm,    -25*mm));
 336   hmp->AddNode(rad,2,new TGeoTranslation(   0*mm,+434*mm, -12.00*mm));
 337   hmp->AddNode(rad,1,new TGeoTranslation(   0*mm,   0*mm, -12.00*mm));
 338   hmp->AddNode(rad,0,new TGeoTranslation(   0*mm,-434*mm, -12.00*mm));
 339     rad->AddNode(neo,1,new TGeoTranslation(   0*mm,   0*mm, -10.0*mm));
 340     rad->AddNode(win,1,new TGeoTranslation(   0*mm,   0*mm,   9.5*mm));
 341     rad->AddNode(si1,1,new TGeoTranslation(   0*mm,-204*mm,  -0.5*mm)); rad->AddNode(si1,2,new TGeoTranslation(   0*mm,+204*mm,  -0.5*mm));
 342     rad->AddNode(si2,1,new TGeoTranslation(-660*mm,   0*mm,  -0.5*mm)); rad->AddNode(si2,2,new TGeoTranslation(+660*mm,   0*mm,  -0.5*mm));
 343     for(Int_t i=0;i<3;i++) for(Int_t j=0;j<10;j++) rad->AddNode(spa,10*i+j,new TGeoTranslation(-1330*mm/2+116*mm+j*122*mm,(i-1)*105*mm,-0.5*mm));
 344   hmp->AddNode(fr4,1,new TGeoTranslation(   0*mm,   0*mm,   9.00*mm));                     //p.84 TDR
 345   for(int i=1;i<=322;i++)  fr4->AddNode(col,i,new TGeoCombiTrans( 0*mm, -1296/2*mm+i*4*mm,-5*mm,rot)); //F4 2043P1
 346                            fr4->AddNode(f4a,1,new TGeoTranslation(   0*mm,0*mm, 2.5*mm));
 347                                         f4a->AddNode(f4i,1,new TGeoTranslation(   0*mm,0*mm,   0*mm));
 348   hmp->AddNode(sec,4,new TGeoTranslation(-335*mm,+433*mm,  78.6*mm)); hmp->AddNode(sec,5,new TGeoTranslation(+335*mm,+433*mm,  78.6*mm));
 349   hmp->AddNode(sec,2,new TGeoTranslation(-335*mm,   0*mm,  78.6*mm)); hmp->AddNode(sec,3,new TGeoTranslation(+335*mm,   0*mm,  78.6*mm));
 350   hmp->AddNode(sec,0,new TGeoTranslation(-335*mm,-433*mm,  78.6*mm)); hmp->AddNode(sec,1,new TGeoTranslation(+335*mm,-433*mm,  78.6*mm));
 351     sec->AddNode(gap,1,new TGeoTranslation(0,0,0.*mm));
 352       cel->AddNode(cat,1,new TGeoCombiTrans (0,  3.15*mm , -2.70*mm , rot)); //4 cathode wires
 353       cel->AddNode(ano,1,new TGeoCombiTrans (0,  2.00*mm , -0.29*mm , rot)); //2 anod wires
 354       cel->AddNode(cat,2,new TGeoCombiTrans (0,  1.05*mm , -2.70*mm , rot));
 355       cel->AddNode(cat,3,new TGeoCombiTrans (0, -1.05*mm , -2.70*mm , rot));
 356       cel->AddNode(ano,2,new TGeoCombiTrans (0, -2.00*mm , -0.29*mm , rot));
 357       cel->AddNode(cat,4,new TGeoCombiTrans (0, -3.15*mm , -2.70*mm , rot));
 358       cel->AddNode(pad,1,new TGeoTranslation(0,  0.00*mm ,  2.25*mm));       //1 pad
 359
 360   hmp->AddNode(fr1,1,new TGeoTranslation(0.,0.,(80.+1.7)*mm+58.3*mm/2.));
 361                 fr1->AddNode(fr1up,1,new TGeoTranslation(0.,0.,(58.3*mm-20.00*mm)/2.));
 362
 363                 fr1->AddNode(fr1perUpBig,0,new TGeoTranslation(0.,(1385-37-35)*mm/2.,(58.3*mm-20.00*2*mm-10.0*mm)/2.));
 364                 fr1->AddNode(fr1perUpSma,0,new TGeoTranslation((1426-37-35)*mm/2.,0.,(58.3*mm-20.00*2*mm-10.0*mm)/2.));
 365                 fr1->AddNode(fr1perUpBig,1,new TGeoTranslation(0.,-(1385-37-35)*mm/2.,(58.3*mm-20.00*2*mm-10.0*mm)/2.));
 366                 fr1->AddNode(fr1perUpSma,1,new TGeoTranslation(-(1426-37-35)*mm/2.,0.,(58.3*mm-20.00*2*mm-10.0*mm)/2.));
 367
 368           fr1->AddNode(fr1perDowBig,0,new TGeoTranslation(0.,(1385-37-46)*mm/2.,(-58.3*mm+2.3*mm)/2.));
 369                 fr1->AddNode(fr1perDowSma,0,new TGeoTranslation((1426-37-46)*mm/2.,0.,(-58.3*mm+2.3*mm)/2.));
 370           fr1->AddNode(fr1perDowBig,1,new TGeoTranslation(0.,-(1385-37-46)*mm/2.,(-58.3*mm+2.3*mm)/2.));
 371                 fr1->AddNode(fr1perDowSma,1,new TGeoTranslation(-(1426-37-46)*mm/2.,0.,(-58.3*mm+2.3*mm)/2.));
 372
 373
 374           fr1->AddNode(ppf,4,new TGeoTranslation(-335*mm,433*mm,(-58.3+38.3)*mm/2.));  fr1->AddNode(ppf,5,new TGeoTranslation(335*mm,433*mm,(-58.3+38.3)*mm/2.));
 375           fr1->AddNode(ppf,2,new TGeoTranslation(-335*mm,0.,(-58.3+38.3)*mm/2.));      fr1->AddNode(ppf,3,new TGeoTranslation(335*mm,0.,(-58.3+38.3)*mm/2.));
 376           fr1->AddNode(ppf,0,new TGeoTranslation(-335*mm,-433*mm,(-58.3+38.3)*mm/2.)); fr1->AddNode(ppf,1,new TGeoTranslation(335*mm,-433*mm,(-58.3+38.3)*mm/2.));
 377
 378
 379
 380
 381
 382
 383 // ^ Y  single cell                                                5.5mm CH4 = 1*mm CsI + 4.45*mm CsI x cath +0.05*mm safety margin
 384 // |      ______________________________
 385 // |     |                              |          ^                            ||
 386 //       |                              | 1.05mm                                ||
 387 // 2.2*mm| xxxxxxxxxxxxxxxxxxxxxxxxxxxx |--              50um  x                || cat shift  x=0mm , y= 3.15mm , z=-2.70mm
 388 //       |                              |                                       ||
 389 //       |                              |                                       ||
 390 // __    |  ..........................  | 2.1mm                    20un .       ||  ano shift x=0mm , y= 2.00mm , z=-0.29mm
 391 //       |                              |                                       ||
 392 //       |                              |                                       ||
 393 //       | xxxxxxxxxxxxxxxxxxxxxxxxxxxx |--                    x                ||  cat shift x=0mm , y= 1.05mm , z=-2.70mm
 394 //       |                              |                                       ||
 395 //       |                              |         8.4mm                         ||
 396 // 4*mm  |                              | 2.1mm                                 ||  pad shift x=0mm , y= 0.00mm , z=2.25*mm
 397 //       |                              |                                       ||
 398 //       |                              |                                       ||
 399 //       | xxxxxxxxxxxxxxxxxxxxxxxxxxxx |--                    x                ||  cat shift x=0mm , y=-1.05mm , z=-2.70mm
 400 //       |                              |                                       ||
 401 //       |                              |                                       ||
 402 // __    |  ..........................  | 2.1mm                         . 2.04mm||  ano shift x=0mm , y=-2.00mm , z=-0.29mm
 403 //       |                              |                                       ||
 404 //       |                              |                                       ||
 405 //       | xxxxxxxxxxxxxxxxxxxxxxxxxxxx |--                    x    4.45mm      ||  cat shift x=0mm , y=-3.15mm , z=-2.70mm
 406 // 2.2*mm|                              |                                       ||
 407 //       |                              | 1.05mm                                ||
 408 //       |______________________________|          v                            ||
 409 //       <             8 mm             >
 410 //                                   ----->X                                 ----->Z
 411   ppf->AddNode(lar,0,new TGeoTranslation(-224.5*mm,-151.875*mm,  0.*mm));
 412   ppf->AddNode(lar,1,new TGeoTranslation(-224.5*mm,- 50.625*mm,  0.*mm));
 413   ppf->AddNode(lar,2,new TGeoTranslation(-224.5*mm,+ 50.625*mm,  0.*mm));
 414   ppf->AddNode(lar,3,new TGeoTranslation(-224.5*mm,+151.875*mm,  0.*mm));
 415   ppf->AddNode(lar,4,new TGeoTranslation(+224.5*mm,-151.875*mm,  0.*mm));
 416   ppf->AddNode(lar,5,new TGeoTranslation(+224.5*mm,- 50.625*mm,  0.*mm));
 417   ppf->AddNode(lar,6,new TGeoTranslation(+224.5*mm,+ 50.625*mm,  0.*mm));
 418   ppf->AddNode(lar,7,new TGeoTranslation(+224.5*mm,+151.875*mm,  0.*mm));
 419   ppf->AddNode(smo,0,new TGeoTranslation(- 65.0*mm,-151.875*mm,  0.*mm));
 420   ppf->AddNode(smo,1,new TGeoTranslation(- 65.0*mm,- 50.625*mm,  0.*mm));
 421   ppf->AddNode(smo,2,new TGeoTranslation(- 65.0*mm,+ 50.625*mm,  0.*mm));
 422   ppf->AddNode(smo,3,new TGeoTranslation(- 65.0*mm,+151.875*mm,  0.*mm));
 423   ppf->AddNode(smo,4,new TGeoTranslation(+ 65.0*mm,-151.875*mm,  0.*mm));
 424   ppf->AddNode(smo,5,new TGeoTranslation(+ 65.0*mm,- 50.625*mm,  0.*mm));
 425   ppf->AddNode(smo,6,new TGeoTranslation(+ 65.0*mm,+ 50.625*mm,  0.*mm));
 426   ppf->AddNode(smo,7,new TGeoTranslation(+ 65.0*mm,+151.875*mm,  0.*mm));
 427
 428 hmp->AddNode(fr3,1,new TGeoTranslation(0.,0.,(80.-29.)*mm-34.*mm/2));
 429          fr3->AddNode( fr3up,1,    new TGeoTranslation(0.,  0.,  7*mm));
 430          fr3->AddNode(fr3down,1,new TGeoTranslation(0.,  0., -10*mm));
 431
 432   AliDebug(1,"Stop v2. HMPID option");
 433 }//CreateGeometry()
 434 //++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 435 void AliHMPIDv2::Init()
 436 {
 437 // This method defines ID for sensitive volumes, i.e. such geometry volumes for which there are if(gMC->CurrentVolID()==XXX)
 438 // statements in StepManager()
 439 // Arguments: none
 440 //   Returns: none
 441   AliDebug(1,"Start v2 HMPID.");
 442   fIdPad     = gMC->VolId("Hpad");
 443   fIdCell    = gMC->VolId("Hcel");
 444   AliDebug(1,"Stop v2 HMPID.");
 445 }
 446 //++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 447 void AliHMPIDv2::DefineOpticalProperties()
 448 {
 449 // Optical properties definition.
 450   const Int_t kNbins=30;       //number of photon energy points
 451   Float_t emin=5.5,emax=8.5;         //Photon energy range,[eV]
 452   Float_t aEckov [kNbins];
 453   Double_t dEckov [kNbins];
 454   Float_t aAbsRad[kNbins], aAbsWin[kNbins], aAbsGap[kNbins], aAbsMet[kNbins];
 455   Float_t aIdxRad[kNbins], aIdxWin[kNbins], aIdxGap[kNbins], aIdxMet[kNbins], aIdxPc[kNbins];
 456   Float_t                                                    aQeAll [kNbins], aQePc [kNbins];
 457   Double_t dReflMet[kNbins], dQePc[kNbins];
 458
 459   TF2 *pRaIF=new TF2("HidxRad","sqrt(1+0.554*(1239.84/x)^2/((1239.84/x)^2-5769)-0.0005*(y-20))"                                       ,emin,emax,0,50); //DiMauro mail temp 0-50 degrees C
 460   TF1 *pWiIF=new TF1("HidxWin","sqrt(1+46.411/(10.666*10.666-x*x)+228.71/(18.125*18.125-x*x))"                                        ,emin,emax);      //SiO2 idx TDR p.35
 461   TF1 *pGaIF=new TF1("HidxGap","1+0.12489e-6/(2.62e-4 - x*x/1239.84/1239.84)"                                                         ,emin,emax);      //?????? from where
 462
 463   TF1 *pRaAF=new TF1("HabsRad","(x<7.8)*(gaus+gaus(3))+(x>=7.8)*0.0001"                                                               ,emin,emax);  //fit from DiMauro data 28.10.03
 464   pRaAF->SetParameters(3.20491e16,-0.00917890,0.742402,3035.37,4.81171,0.626309);
 465   TF1 *pWiAF=new TF1("HabsWin","(x<8.2)*(818.8638-301.0436*x+36.89642*x*x-1.507555*x*x*x)+(x>=8.2)*0.0001"                            ,emin,emax);  //fit from DiMauro data 28.10.03
 466   TF1 *pGaAF=new TF1("HabsGap","(x<7.75)*6512.399+(x>=7.75)*3.90743e-2/(-1.655279e-1+6.307392e-2*x-8.011441e-3*x*x+3.392126e-4*x*x*x)",emin,emax);  //????? from where
 467
 468   TF1 *pQeF =new TF1("Hqe"    ,"0+(x>6.07267)*0.344811*(1-exp(-1.29730*(x-6.07267)))"                                                 ,emin,emax);  //fit from DiMauro data 28.10.03
 469
 470   TString title=GetTitle();
 471   Bool_t isFlatIdx=title.Contains("FlatIdx");
 472
 473   for(Int_t i=0;i<kNbins;i++){
 474     Float_t eV=emin+0.1*i;  //Ckov energy in eV
 475     aEckov [i] =1e-9*eV;    //Ckov energy in GeV
 476     dEckov [i] = aEckov[i];
 477     aAbsRad[i]=pRaAF->Eval(eV); (isFlatIdx)? aIdxRad[i]=1.292: aIdxRad[i]=pRaIF->Eval(eV,20);
 478     aAbsWin[i]=pWiAF->Eval(eV);              aIdxWin[i]=pWiIF->Eval(eV);
 479     aAbsGap[i]=pGaAF->Eval(eV);              aIdxGap[i]=pGaIF->Eval(eV);
 480     aQeAll[i] =1;                     //QE for all other materials except for PC must be 1.
 481     aAbsMet[i] =0.0001;                aIdxMet[i]=0;                                             //metal ref idx must be 0 in order to reflect photon
 482                                        aIdxPc [i]=1;           aQePc [i]=pQeF->Eval(eV);         //PC ref idx must be 1 in order to apply photon to QE conversion
 483     dQePc [i]=pQeF->Eval(eV);
 484     dReflMet[i] = 0.;     // no reflection on the surface of the pc (?)
 485   }
 486   gMC->SetCerenkov((*fIdtmed)[kC6F14]    , kNbins, aEckov, aAbsRad  , aQeAll , aIdxRad );
 487   gMC->SetCerenkov((*fIdtmed)[kSiO2]     , kNbins, aEckov, aAbsWin  , aQeAll , aIdxWin );
 488   gMC->SetCerenkov((*fIdtmed)[kCH4]      , kNbins, aEckov, aAbsGap  , aQeAll , aIdxGap );
 489   gMC->SetCerenkov((*fIdtmed)[kCu]       , kNbins, aEckov, aAbsMet  , aQeAll , aIdxMet );
 490   gMC->SetCerenkov((*fIdtmed)[kW]        , kNbins, aEckov, aAbsMet  , aQeAll , aIdxMet ); //n=0 means reflect photons
 491   gMC->SetCerenkov((*fIdtmed)[kCsI]      , kNbins, aEckov, aAbsMet  , aQePc  , aIdxPc  ); //n=1 means convert photons
 492   gMC->SetCerenkov((*fIdtmed)[kAl]       , kNbins, aEckov, aAbsMet  , aQeAll , aIdxMet );
 493
 494   // Define a skin surface for the photocatode to enable 'detection' in G4
 495   gMC->DefineOpSurface("surfPc", kGlisur /*kUnified*/,kDielectric_metal,kPolished, 0.);
 496   gMC->SetMaterialProperty("surfPc", "EFFICIENCY", kNbins, dEckov, dQePc);
 497   gMC->SetMaterialProperty("surfPc", "REFLECTIVITY", kNbins, dEckov, dReflMet);
 498   gMC->SetSkinSurface("skinPc", "Rpc", "surfPc");
 499
 500   delete pRaAF;delete pWiAF;delete pGaAF; delete pRaIF; delete pWiIF; delete pGaIF; delete pQeF;
 501 }
 502 //++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 503 Bool_t AliHMPIDv2::IsLostByFresnel()
 504 {
 505 // Calculate probability for the photon to be lost by Fresnel reflection.
 506   TLorentzVector p4;
 507   Double_t mom[3],localMom[3];
 508   gMC->TrackMomentum(p4);   mom[0]=p4(1);   mom[1]=p4(2);   mom[2]=p4(3);
 509   localMom[0]=0; localMom[1]=0; localMom[2]=0;
 510   gMC->Gmtod(mom,localMom,2);
 511   Double_t localTc    = localMom[0]*localMom[0]+localMom[2]*localMom[2];
 512   Double_t localTheta = TMath::ATan2(TMath::Sqrt(localTc),localMom[1]);
 513   Double_t cotheta = TMath::Abs(TMath::Cos(localTheta));
 514   if(gMC->GetRandom()->Rndm() < Fresnel(p4.E()*1e9,cotheta,1)){
 515     AliDebug(1,"Photon lost");
 516     return kTRUE;
 517   }else
 518     return kFALSE;
 519 }//IsLostByFresnel()
 520 //++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 521 void AliHMPIDv2::GenFee(Float_t qtot)
 522 {
 523 // Generate FeedBack photons for the current particle. To be invoked from StepManager().
 524 // eloss=0 means photon so only pulse height distribution is to be analysed.
 525   TLorentzVector x4;
 526   gMC->TrackPosition(x4);
 527   Int_t iNphotons=gMC->GetRandom()->Poisson(0.02*qtot);  //# of feedback photons is proportional to the charge of hit
 528   AliDebug(1,Form("N photons=%i",iNphotons));
 529   Int_t j;
 530   Float_t cthf, phif, enfp = 0, sthf, e1[3], e2[3], e3[3], vmod, uswop,dir[3], phi,pol[3], mom[4];
 531 //Generate photons
 532   for(Int_t i=0;i<iNphotons;i++){//feedbacks loop
 533     Double_t ranf[2];
 534     gMC->GetRandom()->RndmArray(2,ranf);    //Sample direction
 535     cthf=ranf[0]*2-1.0;
 536     if(cthf<0) continue;
 537     sthf = TMath::Sqrt((1. - cthf) * (1. + cthf));
 538     phif = ranf[1] * 2 * TMath::Pi();
 539
 540     if(Double_t randomNumber=gMC->GetRandom()->Rndm()<=0.57)
 541       enfp = 7.5e-9;
 542     else if(randomNumber<=0.7)
 543       enfp = 6.4e-9;
 544     else
 545       enfp = 7.9e-9;
 546
 547
 548     dir[0] = sthf * TMath::Sin(phif);    dir[1] = cthf;    dir[2] = sthf * TMath::Cos(phif);
 549     gMC->Gdtom(dir, mom, 2);
 550     mom[0]*=enfp;    mom[1]*=enfp;    mom[2]*=enfp;
 551     mom[3] = TMath::Sqrt(mom[0]*mom[0]+mom[1]*mom[1]+mom[2]*mom[2]);
 552
 553     // Polarisation
 554     e1[0]=      0;    e1[1]=-dir[2];    e1[2]= dir[1];
 555     e2[0]=-dir[1];    e2[1]= dir[0];    e2[2]=      0;
 556     e3[0]= dir[1];    e3[1]=      0;    e3[2]=-dir[0];
 557
 558     vmod=0;
 559     for(j=0;j<3;j++) vmod+=e1[j]*e1[j];
 560     if (!vmod) for(j=0;j<3;j++) {
 561       uswop=e1[j];
 562       e1[j]=e3[j];
 563       e3[j]=uswop;
 564     }
 565     vmod=0;
 566     for(j=0;j<3;j++) vmod+=e2[j]*e2[j];
 567     if (!vmod) for(j=0;j<3;j++) {
 568       uswop=e2[j];
 569       e2[j]=e3[j];
 570       e3[j]=uswop;
 571     }
 572
 573     vmod=0;  for(j=0;j<3;j++) vmod+=e1[j]*e1[j];  vmod=TMath::Sqrt(1/vmod);  for(j=0;j<3;j++) e1[j]*=vmod;
 574     vmod=0;  for(j=0;j<3;j++) vmod+=e2[j]*e2[j];  vmod=TMath::Sqrt(1/vmod);  for(j=0;j<3;j++) e2[j]*=vmod;
 575
 576     phi = gMC->GetRandom()->Rndm()* 2 * TMath::Pi();
 577     for(j=0;j<3;j++) pol[j]=e1[j]*TMath::Sin(phi)+e2[j]*TMath::Cos(phi);
 578     gMC->Gdtom(pol, pol, 2);
 579     Int_t outputNtracksStored;
 580     gAlice->GetMCApp()->PushTrack(1,                             //transport
 581                      gAlice->GetMCApp()->GetCurrentTrackNumber(),//parent track
 582                      50000051,                                   //PID
 583                      mom[0],mom[1],mom[2],mom[3],                //track momentum
 584                      x4.X(),x4.Y(),x4.Z(),x4.T(),                //track origin
 585                      pol[0],pol[1],pol[2],                       //polarization
 586                      kPFeedBackPhoton,                           //process ID
 587                      outputNtracksStored,                        //on return how many new photons stored on stack
 588                      1.0);                                       //weight
 589   }//feedbacks loop
 590   AliDebug(1,"Stop.");
 591 }//GenerateFeedbacks()
 592 //++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 593 void AliHMPIDv2::Hits2SDigits()
 594 {
 595 // Interface method ivoked from AliSimulation to create a list of sdigits corresponding to list of hits. Every hit generates one or more sdigits.
 596 // Arguments: none
 597 //   Returns: none
 598   AliDebug(1,"Start.");
 599   for(Int_t iEvt=0;iEvt < GetLoader()->GetRunLoader()->GetNumberOfEvents();iEvt++){                //events loop
 600     GetLoader()->GetRunLoader()->GetEvent(iEvt);                          //get next event
 601
 602     if(!GetLoader()->TreeH()) {GetLoader()->LoadHits();                    }
 603     if(!GetLoader()->TreeS()) {GetLoader()->MakeTree("S"); MakeBranch("S");}//to
 604
 605     for(Int_t iEnt=0;iEnt<GetLoader()->TreeH()->GetEntries();iEnt++){//prims loop
 606       GetLoader()->TreeH()->GetEntry(iEnt);
 607       Hit2Sdi(Hits(),SdiLst());
 608     }//prims loop
 609     GetLoader()->TreeS()->Fill();
 610     GetLoader()->WriteSDigits("OVERWRITE");
 611     SdiReset();
 612   }//events loop
 613   GetLoader()->UnloadHits();
 614   GetLoader()->UnloadSDigits();
 615   AliDebug(1,"Stop.");
 616 }//Hits2SDigits()
 617 //++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 618 void AliHMPIDv2::Hit2Sdi(TClonesArray *pHitLst,TClonesArray *pSdiLst)
 619 {
 620 // Converts list of hits to list of sdigits.
 621 // Arguments: pHitLst  - list of hits provided not empty
 622 //            pSDigLst - list of sdigits where to store the results
 623 //   Returns: none
 624   for(Int_t iHit=0;iHit<pHitLst->GetEntries();iHit++){         //hits loop
 625     AliHMPIDHit *pHit=(AliHMPIDHit*)pHitLst->At(iHit);         //get pointer to current hit
 626     pHit->Hit2Sdi(pSdiLst);                                    //convert this hit to list of sdigits
 627   }//hits loop loop
 628 }//Hits2Sdi()
 629 //++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 630 void AliHMPIDv2::Digits2Raw()
 631 {
 632 // Interface method invoked by AliSimulation to create raw data streams from digits. Events loop is done in AliSimulation
 633 // Arguments: none
 634 //   Returns: none
 635   AliDebug(1,"Start.");
 636   GetLoader()->LoadDigits();
 637   TTree * treeD = GetLoader()->TreeD();
 638   if(!treeD) {
 639     AliError("No digits tree!");
 640     return;
 641   }
 642   treeD->GetEntry(0);
 643
 644
 645   AliHMPIDRawStream *pRS=0x0;
 646   pRS->WriteRaw(DigLst());
 647
 648   GetLoader()->UnloadDigits();
 649   AliDebug(1,"Stop.");
 650 }//Digits2Raw()
 651 //++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 652 Float_t AliHMPIDv2::Fresnel(Float_t ene,Float_t pdoti, Bool_t pola)
 653 {
 654 // Correction for Fresnel   ???????????
 655 // Arguments:   ene - photon energy [GeV],
 656 //              PDOTI=COS(INC.ANG.), PDOTR=COS(POL.PLANE ROT.ANG.)
 657 //   Returns:
 658     Float_t en[36] = {5.0,5.1,5.2,5.3,5.4,5.5,5.6,5.7,5.8,5.9,6.0,6.1,6.2,
 659                       6.3,6.4,6.5,6.6,6.7,6.8,6.9,7.0,7.1,7.2,7.3,7.4,7.5,7.6,7.7,
 660                       7.8,7.9,8.0,8.1,8.2,8.3,8.4,8.5};
 661     Float_t csin[36] = {2.14,2.21,2.33,2.48,2.76,2.97,2.99,2.59,2.81,3.05,
 662                         2.86,2.53,2.55,2.66,2.79,2.96,3.18,3.05,2.84,2.81,2.38,2.11,
 663                         2.01,2.13,2.39,2.73,3.08,3.15,2.95,2.73,2.56,2.41,2.12,1.95,
 664                         1.72,1.53};
 665     Float_t csik[36] = {0.,0.,0.,0.,0.,0.196,0.408,0.208,0.118,0.49,0.784,0.543,
 666                         0.424,0.404,0.371,0.514,0.922,1.102,1.139,1.376,1.461,1.253,0.878,
 667                         0.69,0.612,0.649,0.824,1.347,1.571,1.678,1.763,1.857,1.824,1.824,
 668                         1.714,1.498};
 669     Float_t xe=ene;
 670     Int_t  j=Int_t(xe*10)-49;
 671     Float_t cn=csin[j]+((csin[j+1]-csin[j])/0.1)*(xe-en[j]);
 672     Float_t ck=csik[j]+((csik[j+1]-csik[j])/0.1)*(xe-en[j]);
 673
 674     //FORMULAE FROM HANDBOOK OF OPTICS, 33.23 OR
 675     //W.R. HUNTER, J.O.S.A. 54 (1964),15 , J.O.S.A. 55(1965),1197
 676
 677     Float_t sinin=TMath::Sqrt((1.-pdoti)*(1.+pdoti));
 678     Float_t tanin=sinin/pdoti;
 679
 680     Float_t c1=cn*cn-ck*ck-sinin*sinin;
 681     Float_t c2=4*cn*cn*ck*ck;
 682     Float_t aO=TMath::Sqrt(0.5*(TMath::Sqrt(c1*c1+c2)+c1));
 683     Float_t b2=0.5*(TMath::Sqrt(c1*c1+c2)-c1);
 684
 685     Float_t rs=((aO-pdoti)*(aO-pdoti)+b2)/((aO+pdoti)*(aO+pdoti)+b2);
 686     Float_t rp=rs*((aO-sinin*tanin)*(aO-sinin*tanin)+b2)/((aO+sinin*tanin)*(aO+sinin*tanin)+b2);
 687
 688
 689     //CORRECTION FACTOR FOR SURFACE ROUGHNESS
 690     //B.J. STAGG  APPLIED OPTICS, 30(1991),4113
 691
 692     Float_t sigraf=18.;
 693     Float_t lamb=1240/ene;
 694     Float_t fresn;
 695
 696     Float_t  rO=TMath::Exp(-(4*TMath::Pi()*pdoti*sigraf/lamb)*(4*TMath::Pi()*pdoti*sigraf/lamb));
 697
 698     if(pola)
 699     {
 700         Float_t pdotr=0.8;                                 //DEGREE OF POLARIZATION : 1->P , -1->S
 701         fresn=0.5*(rp*(1+pdotr)+rs*(1-pdotr));
 702     }
 703     else
 704         fresn=0.5*(rp+rs);
 705
 706     fresn = fresn*rO;
 707     return fresn;
 708 }//Fresnel()
 709 //++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 710 void AliHMPIDv2::Print(Option_t *option)const
 711 {
 712 // Debug printout
 713   TObject::Print(option);
 714 }//void AliHMPID::Print(Option_t *option)const
 715 //++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 716 Bool_t AliHMPIDv2::Raw2SDigits(AliRawReader *pRR)
 717 {
 718 // Interface methode ivoked from AliSimulation to create a list of sdigits from raw digits. Events loop is done in AliSimulation
 719 // Arguments: pRR- raw reader
 720 //   Returns: kTRUE on success (currently ignored in AliSimulation::ConvertRaw2SDigits())
 721   //AliHMPIDDigit sdi; //tmp sdigit, raw digit will be converted to it
 722
 723   if(!GetLoader()->TreeS()) {MakeTree("S");  MakeBranch("S");}
 724
 725   TClonesArray *pSdiLst=SdiLst(); Int_t iSdiCnt=0; //tmp list of sdigits for all chambers
 726   AliHMPIDRawStream stream(pRR);
 727   while(stream.Next())
 728   {
 729     for(Int_t iPad=0;iPad<stream.GetNPads();iPad++) {
 730       AliHMPIDDigit sdi(stream.GetPadArray()[iPad],stream.GetChargeArray()[iPad]);
 731       new((*pSdiLst)[iSdiCnt++]) AliHMPIDDigit(sdi); //add this digit to the tmp list
 732     }
 733   }
 734
 735   GetLoader()->TreeS()->Fill(); GetLoader()->WriteSDigits("OVERWRITE");//write out sdigits
 736   SdiReset();
 737   return kTRUE;
 738 }//Raw2SDigits
 739 //++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 740 void AliHMPIDv2::StepCount()
 741 {
 742 // Count number of ckovs created
 743 }
 744 //++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 745 void AliHMPIDv2::StepHistory()
 746 {
 747 // This methode is invoked from StepManager() in order to print out
 748   static Int_t iStepN;
 749   const char *sParticle;
 750   switch(gMC->TrackPid()){
 751     case kProton:      sParticle="PROTON"    ;break;
 752     case kNeutron:     sParticle="neutron"   ;break;
 753     case kGamma:       sParticle="gamma"     ;break;
 754     case 50000050:     sParticle="CKOV"      ;break;
 755     case kPi0:         sParticle="Pi0"       ;break;
 756     case kPiPlus:      sParticle="Pi+"       ;break;
 757     case kPiMinus:     sParticle="Pi-"       ;break;
 758     case kElectron:    sParticle="electron"  ;break;
 759     default:           sParticle="not known" ;break;
 760   }
 761
 762   TString flag="fanny combination";
 763   if(gMC->IsTrackAlive()) {
 764     if(gMC->IsTrackEntering())      flag="enters to";
 765     else if(gMC->IsTrackExiting())  flag="exits from";
 766     else if(gMC->IsTrackInside())   flag="inside";
 767   } else {
 768     if(gMC->IsTrackStop())          flag="stopped in";
 769   }
 770
 771   Int_t vid=0,copy=0;
 772   TString path=gMC->CurrentVolName(); path.Prepend("-");path.Prepend(gMC->CurrentVolOffName(1));//current volume and his mother are always there
 773   vid=gMC->CurrentVolOffID(2,copy);  if(vid) {path.Prepend("-");path.Prepend(gMC->VolName(vid));}
 774   vid=gMC->CurrentVolOffID(3,copy);  if(vid) {path.Prepend("-");path.Prepend(gMC->VolName(vid));}
 775
 776
 777   Printf("Step %i: %s (%i) %s %s m=%.6f GeV q=%.1f dEdX=%.4f Etot=%.4f",iStepN,sParticle,gMC->TrackPid(),flag.Data(),path.Data(),gMC->TrackMass(),gMC->TrackCharge(),gMC->Edep()*1e9,gMC->Etot());
 778
 779   Double_t gMcTrackPos[3]; gMC->TrackPosition(gMcTrackPos[0],gMcTrackPos[1],gMcTrackPos[2]);
 780   Double_t  gMcTrackPosLoc[3]; gMC->Gmtod(gMcTrackPos,gMcTrackPosLoc,1);
 781   Printf("gMC Track Position (MARS) x: %5.3lf, y: %5.3lf, z: %5.3lf (r: %5.3lf) ---> (LOC) x: %5.3f, y: %5.3f, z: %5.3f",gMcTrackPos[0],gMcTrackPos[1],gMcTrackPos[2],TMath::Sqrt(gMcTrackPos[0]*gMcTrackPos[0]+gMcTrackPos[1]*gMcTrackPos[1]+gMcTrackPos[2]*gMcTrackPos[2]),gMcTrackPosLoc[0],gMcTrackPosLoc[1],gMcTrackPosLoc[2]);
 782
 783
 784
 785   Printf("Step %i: tid=%i flags alive=%i disap=%i enter=%i exit=%i inside=%i out=%i stop=%i new=%i",
 786                             iStepN, gAlice->GetMCApp()->GetCurrentTrackNumber(),
 787                             gMC->IsTrackAlive(), gMC->IsTrackDisappeared(),gMC->IsTrackEntering(), gMC->IsTrackExiting(),
 788                             gMC->IsTrackInside(),gMC->IsTrackOut(),        gMC->IsTrackStop(),     gMC->IsNewTrack());
 789
 790   Float_t a,z,den,rad,abs; a=z=den=rad=abs=-1;
 791   Int_t mid=gMC->CurrentMaterial(a,z,den,rad,abs);
 792   Printf("Step %i: mid=%i a=%7.2f z=%7.2f den=%9.4f rad=%9.2f abs=%9.2f\n\n",iStepN,mid,a,z,den,rad,abs);
 793
 794   TArrayI proc;  gMC->StepProcesses(proc);
 795   Printf("Processes in this step:");
 796   for ( int i = 0 ; i < proc.GetSize(); i++)
 797   {
 798     Printf("%s",TMCProcessName[proc.At(i)]);
 799   }
 800   Printf("End process list");
 801
 802   iStepN++;
 803 }//StepHistory()
 804 //++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 805 void AliHMPIDv2::StepManager()
 806 {
 807 // Full Step Manager.
 808 // Arguments: none
 809 //   Returns: none
 810 //  StepHistory(); return; //uncomment to print tracks history
 811  //  StepCount(); return;     //uncomment to count photons
 812
 813   Int_t   copy; //volume copy aka node
 814
 815 //Treat photons
 816   if((gMC->TrackPid()==50000050||gMC->TrackPid()==50000051)&&gMC->CurrentVolID(copy)==fIdPad){   //photon (Ckov or feedback) hit PC (fIdPad)
 817     if(gMC->Edep()>0){                                                                           //photon survided QE test i.e. produces electron
 818       if(IsLostByFresnel()){ gMC->StopTrack(); return;}                                          //photon lost due to fersnel reflection on PC
 819                        gMC->CurrentVolOffID(5,copy);                                             //current chamber since geomtry tree is Hmp-Hsec-Hgap-Hrow-Hcel-Hpad
 820       Int_t   tid=     gMC->GetStack()->GetCurrentTrackNumber();                                 //take TID
 821       Int_t   pid=     gMC->TrackPid();                                                          //take PID
 822       Float_t etot=    gMC->Etot();                                                              //total hpoton energy, [GeV]
 823       Double_t x[3];   gMC->TrackPosition(x[0],x[1],x[2]);                                       //take MARS position at entrance to PC
 824       Float_t hitTime= (Float_t)gMC->TrackTime();                                                         //hit formation time
 825       Float_t xl,yl;   AliHMPIDParam::Instance()->Mars2Lors(copy,x,xl,yl);                       //take LORS position
 826       new((*fHits)[fNhits++])AliHMPIDHit(copy,etot,pid,tid,xl,yl,hitTime,x);                             //HIT for photon, position at P, etot will be set to Q
 827       if(fDoFeed) GenFee(etot);                                                                  //generate feedback photons etot is modified in hit ctor to Q of hit
 828     }//photon hit PC and DE >0
 829   }//photon hit PC
 830
 831 //Treat charged particles
 832   static Float_t eloss;                                                                           //need to store mip parameters between different steps
 833   static Double_t in[3];
 834   if(gMC->IsTrackEntering() && gMC->TrackCharge() && gMC->CurrentVolID(copy)==fIdPad)             //Trackref stored when entering in the pad volume
 835     AddTrackReference(gMC->GetStack()->GetCurrentTrackNumber(), AliTrackReference::kHMPID);       //for acceptance calculations
 836   if(gMC->TrackCharge() && gMC->CurrentVolID(copy)==fIdCell){                                     //charged particle in amplification gap (fIdCell)
 837     if(gMC->IsTrackEntering()||gMC->IsNewTrack()) {                                               //entering or newly created
 838       eloss=0;                                                                                    //reset Eloss collector
 839       gMC->TrackPosition(in[0],in[1],in[2]);                                                      //take position at the entrance
 840     }else if(gMC->IsTrackExiting()||gMC->IsTrackStop()||gMC->IsTrackDisappeared()){               //exiting or disappeared
 841       eloss              +=gMC->Edep();                                                           //take into account last step Eloss
 842                           gMC->CurrentVolOffID(4,copy);                                           //take current chamber since geometry tree is Hmp-Hsec-Hgap-Hrow-Hcel
 843       Int_t tid=          gMC->GetStack()->GetCurrentTrackNumber();                               //take TID
 844       Int_t pid=          gMC->TrackPid();                                                        //take PID
 845       Double_t out[3];    gMC->TrackPosition(out[0],out[1],out[2]);                               //take MARS position at exit
 846       Float_t hitTime= (Float_t)gMC->TrackTime();                                                         //hit formation time
 847       out[0]=0.5*(out[0]+in[0]);                                                                  //>
 848       out[1]=0.5*(out[1]+in[1]);                                                                  //take hit position at the anod plane
 849       out[2]=0.5*(out[2]+in[2]);                                                                  //>
 850       Float_t xl,yl;AliHMPIDParam::Instance()->Mars2Lors(copy,out,xl,yl);                         //take LORS position
 851       new((*fHits)[fNhits++])AliHMPIDHit(copy,eloss,pid,tid,xl,yl,hitTime,out);                   //HIT for MIP, position near anod plane, eloss will be set to Q
 852       if(fDoFeed) GenFee(eloss);                                                                  //generate feedback photons
 853     }else                                                                                         //just going inside
 854       eloss          += gMC->Edep();                                                              //collect this step eloss
 855   }//MIP in GAP
 856 }//StepManager()
 857 //++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 858 void AliHMPIDv2::TestPoint(Int_t ch,Float_t x,Float_t y)
 859 {
 860 // Utility method to check the validity of geometry by poviding some crucial points
 861 // Arguments: ch,x,y- crucial point definition (cm) in LORS
 862 //   Returns: none
 863   Double_t mars[3];
 864   AliHMPIDParam::Instance()->Lors2Mars(ch,x,y,mars);
 865   Printf("(ch=%i,locX=%.2f,locY=%.2f) %s",ch,x,y,gGeoManager->FindNode(mars[0],mars[1],mars[2])->GetName());
 866 }//TestPoint()
 867 //++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 868 void AliHMPIDv2::TestGeom()
 869 {
 870 //
 871 // Test method to check geometry
 872 //
 873   //TGeoManager::Import("misaligned_geometry.root");
 874   TGeoManager::Import("geometry.root");
 875   for(Int_t ch=AliHMPIDParam::kMinCh;ch<=AliHMPIDParam::kMaxCh;ch++)
 876     TestPoint(ch,0,0);
 877 }//TestPoint()
 878 //+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 879
 880 void  AliHMPIDv2::IdealPosition(Int_t iCh,TGeoHMatrix *pMatrix)       //ideal position of given chamber
 881 {
 882 // Construct ideal position matrix for a given chamber
 883 // Arguments: iCh- chamber ID; pMatrix- pointer to precreated unity matrix where to store the results
 884 //   Returns: none
 885   const Double_t kAngHor=19.5;        //  horizontal angle between chambers  19.5 grad
 886   const Double_t kAngVer=20;          //  vertical angle between chambers    20   grad
 887   const Double_t kAngCom=30;          //  common HMPID rotation with respect to x axis  30   grad
 888   const Double_t kTrans[3]={490,0,0}; //  center of the chamber is on window-gap surface
 889   pMatrix->RotateY(90);               //  rotate around y since initial position is in XY plane -> now in YZ plane
 890   pMatrix->SetTranslation(kTrans);    //  now plane in YZ is shifted along x
 891   switch(iCh){
 892     case 0:                pMatrix->RotateY(kAngHor);  pMatrix->RotateZ(-kAngVer);  break; //right and down
 893     case 1:                                            pMatrix->RotateZ(-kAngVer);  break; //down
 894     case 2:                pMatrix->RotateY(kAngHor);                               break; //right
 895     case 3:                                                                         break; //no rotation
 896     case 4:                pMatrix->RotateY(-kAngHor);                              break; //left
 897     case 5:                                            pMatrix->RotateZ(kAngVer);   break; //up
 898     case 6:                pMatrix->RotateY(-kAngHor); pMatrix->RotateZ(kAngVer);   break; //left and up
 899   }
 900   pMatrix->RotateZ(kAngCom);     //apply common rotation  in XY plane
 901 }